This invention relates to marine propellers, and more particularly to a marine propeller having a geometry resistant to cavitation and ventilation at high speed operation.
The function of marine propellers is based upon rather basic principles which have been generally accepted for many decades. Effective results from the rotating propeller depend upon maintaining optimum pressure differential between the front and back of the individual blades. Application of the basic propeller principles to actual operating conditions, however, involves the interplay of many complex variables resulting from the multidirectional fluid flow, vapor pressure factors, induction of air, and the interaction of these caused by the three dimensional, complexly configurated surfaces of the propeller. Consequently, the effective functioning of what would seem to be theoretically simple, is actually extremely complex, especially at high operational speeds, as is well known to those in this art. Therefore, propeller designers constantly experiment with propeller variations, and periodically discover hub or blade geometries that empirically function unexpectedly well, or unexpectedly poorly, for reasons that are not fully understood. As with the present invention, this sometimes occurs after long periods of trial and error experimentation with different configuration variations.